- directory as the kernel file. This file is a practical requirement for
- booting from an auto-detected kernel. It consists of a series of lines,
- each of which consists of a label followed by a series of kernel
- options. The first line sets default options, and subsequent lines set
- options that are accessible from the main menu tag's submenu screen. If
- you installed rEFInd 0.5.1 or later with the <tt>install.sh</tt>
- script, that script created a sample <tt>refind_linux.conf</tt> file,
- customized for your computer, in <tt>/boot</tt>. This file will work
- without changes on many installations, but you may need to tweak it for
- some.</li>
+ directory as the kernel file. It consists of a series of lines, each of
+ which consists of a label followed by a series of kernel options. The
+ first line sets default options, and subsequent lines set options that
+ are accessible from the main menu tag's submenu screen. If you installed
+ rEFInd with the <tt>refind-install</tt> script, that script created a
+ sample <tt>refind_linux.conf</tt> file, customized for your computer, in
+ <tt>/boot</tt>. This file will work without changes on many
+ installations, but you may need to tweak it for some. If the kernel
+ options string includes the substring <tt>%v</tt>, rEFInd substitutes
+ the kernel version number for that string. (If you need the actual
+ string <tt>%v</tt> in your kernel options, use <tt>%%v</tt> instead;
+ rEFInd will change this to <tt>%v</tt>.) This feature can be used to
+ match an initial RAM disk file that requires special treatment, such as
+ if you have multiple numbered kernels, each of which has two initial RAM
+ disk files.</li>
+
+<li>If rEFInd can't find a <tt>refind_linux.conf</tt> file in the directory
+ that holds the kernel, the program looks for a file called
+ <tt>/etc/fstab</tt> on the partition that holds the kernel. If this
+ standard Linux file is present, rEFInd uses it to identify the root
+ (<tt>/</tt>) filesystem and creates two sets of Linux kernel boot
+ options: One set launches the kernel normally, but with minimal
+ options, and the other set launches the kernel into single-user mode.
+ This step can get a computer to boot without any rEFInd-specific
+ configuration files, aside from <tt>refind.conf</tt> in rEFInd's own
+ directory, but only if <tt>/boot</tt> is not a separate partition. The
+ intent is to facilitate the use of rEFInd as an emergency boot manager
+ or to help users who must install rEFInd from OS X or Windows. Note
+ that rEFInd uses <tt>/etc/fstab</tt> only if <tt>refind_linux.conf</tt>
+ is <i>not</i> found.</li>
+
+<li>If rEFInd can't find a <tt>refind_linux.conf</tt> file or an
+ <tt>/etc/fstab</tt> file, it tries to identify the Linux root
+ (<tt>/</tt>) filesystem by looking for a partition with a GUID type code
+ matching that specified for the root (<tt>/</tt>) filesystem in the <a
+ href="http://www.freedesktop.org/wiki/Specifications/DiscoverablePartitionsSpec/">Freedesktop.org
+ Discoverable Partitions Specification.</a> These type codes are as yet
+ seldom used, but if and when they become common, they should help a lot
+ for situations similar to those of the preceding case, but when a
+ separate <tt>/boot</tt> partition is used.</li>